Conventional power systems for engines, factories, and power plants produce emissions that contain a variety of pollutants. These pollutants may include, for example, particulate matter (e.g., soot), nitrogen oxides (NOx), and sulfur compounds. Due to heightened environmental concerns, engine exhaust emission standards have become increasingly stringent. In order to comply with emission standards, machine manufactures have developed and implemented a variety of exhaust treatment components to reduce pollutants in exhaust gas prior to the exhaust gas being released into the atmosphere.
The exhaust treatment components may include, for example, a diesel particulate filter, a selective catalytic reduction device, a diesel oxidation catalyst, a heat source for regeneration of the diesel particulate filter, a muffler, and other similar components. Packaging of these exhaust treatment components is difficult and is often particularly difficult given the temperatures or heat involved. The devises and environment surrounding these exhaust treatment components may not be able to withstand this heat.
U.S. Pat. No. 7,127,884 (the '884 patent) describes multiple catalytic converter elements in a housing. The housing includes a jacket with a double wall.